Malicious PDF — malware analysis report

Static analysis result for SHA-256 83cb897f53bb84fc…

MALICIOUS

PDF

81.2 KB Created: 2021-04-07 06:30:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: d4c09e6b75a16ce09862be6185ab786d SHA-1: c12af53c7030ad996583e99f66242e8d105b18f2 SHA-256: 83cb897f53bb84fc68c97fc498128504223d32370b469fabf17247d70a59391c
184 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm and routes users through malicious redirector infrastructure. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://yafferge.ru/award?keyword=keto+meal+plan+for+weight+loss+pdf In PDF document text
    • https://static.s123-cdn-static.com/uploads/4401525/normal_5fedd01a4f705.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4480393/normal_5fec77d31f03b.pdfIn PDF document text
    • https://cdn.sqhk.co/laratakidev/LbhbtPP/74393286794.pdfIn PDF document text
    • http://nubebukexowi.66ghz.com/14359246778.pdfIn PDF document text
    • http://draiwenstore.online/puwal83rph.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473926/normal_5fe497fdb7609.pdfIn PDF document text
    • https://cdn.sqhk.co/naliwanik/vXWhdjh/11758718329.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482882/normal_6064c5808984b.pdfIn PDF document text
    • http://fortuneo.biz/2777286721445vgb.pdfIn PDF document text
    • http://paksorond.xyz/839179081640g1nk.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/b9ccf5cc-f8aa-4e7a-a140-699dc849b7d5/what_is_bosch_tall_tub_dishwasher.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/48a94f10-8983-46b3-b4a3-003f016e6ebd/sexazaw.pdfIn PDF document text
    • http://zibakogemigana.rf.gd/jelosudoropi.pdfIn PDF document text
    • https://8458b573-1d6d-478c-912c-b10a972f31df.filesusr.com/ugd/150112_331733d3e63d4aa49fcf3cb47bb37cf8.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b5e82edc-bf8f-485e-9e97-8b3eb57d0ad6/how_do_i_charge_my_stanley_jump_starter.pdfIn PDF document text
    • https://ecab545c-19d2-4654-b6ac-fb8b9749f5ba.filesusr.com/ugd/e5412a_3fc74f48b0e54303a1de490788ad7153.pdf?index=trueIn PDF document text
    • http://fivamoxopel.epizy.com/72745255535.pdfIn PDF document text
    • https://b6f97e74-198a-461d-a312-d71b9712332b.filesusr.com/ugd/a2d007_40eec312bc4a40f2a0ae1522d2f00f44.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f721.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF721 5516 bytes
SHA-256: 9c279eebd016dd9c3bf6244f43f7dfaaaa8b3d19144a981dbf015cc0c607fcca
font_01_sfnt_off000109c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109C4 1800 bytes
SHA-256: e9a5a1f6ed95b1e3669933bb00002ad32a1708c3e0b735191cad5e02368a6c7d
font_02_sfnt_off00011252.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11252 10872 bytes
SHA-256: 63a203b31abb43589188ebe4d2dd06368fcf501768fe03f0edabf40423491e90